We know, after Joseph Parker climbed off the canvas twice against Dillian Whyte, that the New Zealand heavyweight can handle adversity – a key attribute in boxing and in this division in particular. Now, if he is to remain among the top echelon, we need to see if he can stop an opponent again.
He is still in the increasingly complicated mix. The respected The Ring magazine recently ranked him as the seventh best heavyweight in the world, with Tyson Fury the big mover to No2 (behind WBA, WBO and IBF world champion Anthony Joshua and ahead of WBC champion Deontay Wilder).
All three – Joshua, Fury and Wilder – have shown an ability to dig deep and survive (and in two cases flourish) after being in very difficult positions.
Joshua climbed off the canvas to knock out Wladimir Klitschko in his coming-of-age fight at Wembley a year ago, Wilder was hurt against Luis Ortiz this year but stopped the Cuban, and Fury in perhaps the most remarkable performance of all, somehow got up after being knocked down by Wilder in the 12th round of their fight in Los Angeles last weekend to draw a fight most thought he won.
Parker, who will fight Alexander Flores in Christchurch on Saturday, was asked to try to explain how Fury got up after being hit in both temples by the hardest puncher in the sport.
"Listen, I didn't think he was going to get up so I can't really explain what he was going through," Parker said. "It looked like he was out for the count. It shows the willpower that he has.
"He mentioned as well he was doing it for himself and his family and everyone who has been through what he has been through. There was a lot more behind the scenes that he was fighting for – not only for himself and his career."
It's clear that Parker, officially ranked No5 by the WBC, has the toughness and mental resolve required to mix it with the best. He went 12 rounds against Joshua in Cardiff without being hurt and responded to the concussive blow caused by the accidental headbutt in the second round against Whyte at London's O2 Arena and a legitimate knockdown in the ninth to flatten the Englishman in the 12th and nearly steal the victory.
Now he has to beat Flores at the Horncastle Arena with an early and decisive stoppage. To that end he has concentrated on his power far more than at any other stage in his career.
Trainer Kevin Barry was understood to be wary about allowing Parker to push big weights and concentrate too much on power conditioning lest it interfere with his hand speed which is among the fastest in the division.
But Parker hasn't stopped an opponent since Alexander Dimitrenko five fights and 26 months ago. That was in Auckland two months before he won the WBO world championship with a majority decision victory over Andy Ruiz Jr.
So there has been an acceptance that something had to change. Parker has shown in training over the past couple of weeks in particular that he is now bigger and stronger and willing to fight dirty if he has to in a division full of very big, strong and ruthless men.
The confident Flores, a Mexican-American, has promised a stoppage but while the fight is unlikely to go the full 12 rounds, it's even unlikelier that he will be the man winning by knockout.
The Ring heavyweight rankings:
1. Anthony Joshua (Eng)
2. Tyson Fury (Eng)
3. Deontay Wilder (USA)
4. Luis Ortiz (Cuba)
5. Dillian Whyte (Eng)
6. Alexander Povetkin (Russia)
7. Joseph Parker (NZ)
8. Jarrell Miller (USA)
9. Adam Kownacki (USA)
10. Kubrat Pulev (Bulgaria)